Furfuryl alcohol is an important chemical, mainly used for the production of resins for bonding foundry sand to produce cores and molds for metal casting, corrosion-resistant mortar for installing acid proof brick, laminating resins for corrosion resistant fiberglass-reinforced equipment, resins for corrosion resistant furan polymer concrete, impregnating solutions and carbon binders. It is also used as nonreactive diluent for epoxy resins, modifier for phenolic and urea resins, oil-well sand consolidation, solvent, production of tetrahydro furfuryl alcohol and other chemical synthesis. It is also an important chemical intermediate for the manufacture of lysine, vitamin C, lubricant, dispersing agent and plastisizer.
Cyclohexanone is an industrially important chemical for the manufacture of caprolactum and adipic acid which are used in producing polyamide fiber in nylon-textiles.
Industrially, furfuryl alcohol is produced by hydrogenation of furfural either in liquid phase or in vapor phase. On the other hand, cyclohexanone is produced majorily in vapor phase by dehydrogenation of cyclohexanol. Both the processes employ copper based catalysts.
A number of methods are reported in patent literature on the preparation of catalysts useful for the separate hydrogenation of furfural and dehydrogenation of cyclohexanol.
Liquid phase hydrogenation of furfural under a pressure of 30 atm. over copper chromite catalysts were disclosed in U.S. Pat. Nos. 4,251,396, 4,302,397. Chinese patent CN1404922 discloses a catalyst comprising of CuO—Cr2O3—NiO for the liquid phase hydrogenation of furfural at 35 to 50 atm. and in the temperature range of 453–473 K. The vapor phase hydrogenation of furfural was disclosed in U.S. Pat. Nos. 4,261,905 and 5,591,873 wherein copper chromite promoted with alkali earth metals and copper deposited on pyrogenic SiO2 respectively were employed as catalysts. In both the cases the reaction was carried out under pressure.
Vapour phase dehydrogenation of cyclohexanol to produce cyclohexanone over Cu—Cr based catalysts are disclosed in KR8300880 and U.S. Pat. No. 4,310,703. Processes for making Cu/ZnO or Cu/SiO2 with promoters, suitable for dehydrogenation of cyclohexanol were disclosed in JP2000288395, RU210183, U.S. 2004087815, WO09810864. Process for making a multicomponent Cu based cyclohexanol dehydrogenation catalyst was disclosed in CN1056067. A process for making Cu on MgO with promoters for dehydrogenation reaction was disclosed in CN1235870. Liquid phase dehydrogenation of cycloheaxanol under pressure was disclosed in Chinese patent CN1381434 and the corresponding method for catalyst making was disclosed in another Chinese patent CN1381435. A process for making a non Cu based catalyst comprising of ZnO—CaO or CaCO3—Cr2O3 is disclosed in U.S. Pat. No. 6,376,422.
A process for making Cu based catalyst suitable for both hydrogenation and a dehydrogenation process separately was disclosed in GB patent 1097819.
The main drawbacks of the furfural hydrogenation processes mentioned above are that they require either to be operated under pressure or to use large amount of hydrogen along with furfural. Even though both furfural hydrogenation and cyclohexanol dehydrogenation processes employ mostly Cu based catalysts, there are no reports on the combined or simultaneous study of these two processes over a single catalyst system.